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1
10 package com.triactive.jdo.store;
11
12 import com.triactive.jdo.PersistenceManager;
13 import com.triactive.jdo.StateManager;
14 import java.io.InputStream  ;
15 import java.io.OutputStream ;
16 import java.io.IOException ;
17 import java.sql.Connection ;
18 import java.sql.PreparedStatement ;
19 import java.sql.ResultSet ;
20 import java.sql.SQLException ;
21 import java.sql.Types ;
22 import javax.jdo.JDODataStoreException;
23 import javax.jdo.JDOFatalInternalException;
24 import oracle.sql.BLOB;
25 import org.apache.log4j.Category;
26
27
28 public class OracleBlobMapping extends ByteArrayMapping implements PostInsertProcessing, PostUpdateProcessing
29 {
30 private static final Category LOG = Category.getInstance(OracleBlobMapping.class);
31
32 private final ClassBaseTable table;
33 private ColumnMapping idMapping = null;
34 private String fetchStmt = null;
35 private String updateStmt = null;
36
37
38 public OracleBlobMapping(DatabaseAdapter dba, Class type)
39 {
40 super(dba, type);
41
42 this.table = null;
43 }
44
45
46 public OracleBlobMapping(Column col)
47 {
48 super(col);
49
50 this.table = null;
51 }
52
53
54 public OracleBlobMapping(ClassBaseTable table, int relativeFieldNumber)
55 {
56 super(table.newColumn(relativeFieldNumber));
57
58 col.setUnlimitedLength();
59
60 this.table = table;
61 }
62
63
64 private synchronized void initialize()
65 {
66 if (idMapping == null)
67 {
68 if (table == null)
69 throw new JDOFatalInternalException("Not mapped to class base table: " + this);
70
71 idMapping = table.getIDMapping();
72
73 FetchStatement stmt = new FetchStatement(table);
74 stmt.select(getColumn());
75 stmt.andCondition(stmt.referenceColumn(idMapping.getColumn()) + " = ?");
76
77 fetchStmt = stmt.toString() + " FOR UPDATE";
78
79 updateStmt = "UPDATE " + table.getName() + " SET " + col.getName() + " = NULL WHERE " + idMapping.getColumn().getName() + " = ?";
80
81 }
82 }
83
84
85 protected TypeInfo getTypeInfo()
86 {
87 return dba.getTypeInfo(Types.BLOB);
88 }
89
90
91 public String getSQLInsertionValue()
92 {
93 return "EMPTY_BLOB()";
94 }
95
96
97 public String getSQLUpdateValue()
98 {
99 return "EMPTY_BLOB()";
100 }
101
102
103 public void setObject(PersistenceManager pm, PreparedStatement ps, int param, Object value)
104 {
105 }
107
108
109 public Object getObject(PersistenceManager pm, ResultSet rs, int param)
110 {
111 byte[] value = null;
112
113 try
114 {
115 BLOB blob = (BLOB)rs.getBlob(param);
116
117 if (!rs.wasNull() && blob != null)
118 {
119 int len = (int)Math.min(blob.length(), Integer.MAX_VALUE);
120 value = new byte[len];
121
122 try
123 {
124 InputStream in = blob.getBinaryStream();
125
126 try
127 {
128 int off = 0;
129
130 while (off < len)
131 {
132 int n = in.read(value, off, len - off);
133
134 if (n < 0)
135 throw new SQLException ("Premature end-of-BLOB, expected " + len + ", got " + off);
136
137 off += n;
138 }
139 }
140 finally
141 {
142 in.close();
143 }
144 }
145 catch (IOException e)
146 {
147 throw new JDODataStoreException("Error reading Oracle BLOB object: param = " + param, e);
148 }
149 }
150 }
151 catch (SQLException e)
152 {
153 throw dba.newDataStoreException("Can't get byte[] result: param = " + param, e);
154 }
155
156 return value;
157 }
158
159
160 public void postInsert(StateManager sm, Connection conn, Object value)
161 {
162 postUpdate(sm, conn, value);
163 }
164
165
166
170 public void postUpdate(StateManager sm, Connection conn, Object value)
171 {
172 initialize();
173
174 byte[] ba = (byte[])value;
175
176
181 if (ba == null)
182 updateAsNull(sm, conn);
183 else
184 updateWithValue(sm, conn, ba);
185 }
186
187
188 private void updateAsNull(StateManager sm, Connection conn)
189 {
190 PersistenceManager pm = sm.getPersistenceManager();
191
192 try
193 {
194 PreparedStatement ps = conn.prepareStatement(updateStmt);
195
196 try
197 {
198 Object id = sm.getObjectId();
199 idMapping.setObject(pm, ps, 1, id);
200
201 long startTime = System.currentTimeMillis();
202
203 ps.executeUpdate();
204
205 if (LOG.isDebugEnabled())
206 LOG.debug("Time = " + (System.currentTimeMillis() - startTime) + " ms: " + updateStmt);
207 }
208 finally
209 {
210 ps.close();
211 }
212 }
213 catch (SQLException e)
214 {
215 throw dba.newDataStoreException("BLOB update failed: " + updateStmt, e);
216 }
217 }
218
219
220 private void updateWithValue(StateManager sm, Connection conn, byte[] value)
221 {
222 PersistenceManager pm = sm.getPersistenceManager();
223
224 try
225 {
226 PreparedStatement ps = conn.prepareStatement(fetchStmt);
227
228 try
229 {
230 Object id = sm.getObjectId();
231 idMapping.setObject(pm, ps, 1, id);
232
233 long startTime = System.currentTimeMillis();
234
235 ResultSet rs = ps.executeQuery();
236
237 try
238 {
239 if (LOG.isDebugEnabled())
240 LOG.debug("Time = " + (System.currentTimeMillis() - startTime) + " ms: " + fetchStmt);
241
242 if (!rs.next())
243 throw new ObjectNotFoundException("No such database row", sm.getObject());
244
245 BLOB blob = (BLOB)rs.getBlob(1);
246
247 try
248 {
249 OutputStream out = blob.getBinaryOutputStream();
250
251 try
252 {
253 out.write(value);
254 }
255 finally
256 {
257 out.close();
258 }
259 }
260 catch (IOException e)
261 {
262 throw new JDODataStoreException("Error writing Oracle BLOB object", e);
263 }
264 }
265 finally
266 {
267 rs.close();
268 }
269 }
270 finally
271 {
272 ps.close();
273 }
274 }
275 catch (SQLException e)
276 {
277 throw dba.newDataStoreException("BLOB update failed: " + fetchStmt, e);
278 }
279 }
280 }
281 |
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